GP-8 and GP-10 are not an EMD locomotive models. The terms GP-8 and GP-10 were coined to describe very thoroughly rebuilt GP-7 and GP-9 locomotives. By the 1970's, large numbers of the early fleets of diesel locomotives that replaced steam in the 1950's were reaching the end of their service life. The 1970's were a time of economic recession, especially among the railroads. The cash-strapped Illinois Central Gulf railroad began rebuilding first generation GP-7 and GP-9 locomotives to like new condition at its Paducah, Kentucky shops in lieu of purchasing new power. These rebuilds included modern electrical, control, and braking systems. External differences were chopped front hoods, new paper cartridge air filters, and plated over or removed dynamic brake blisters. Other railroads saw the benefits of such an economical solution and soon Paducah was rebuilding locomotives for other railroads. Other rebuilders soon entered the market. Conrail's GP-8 and GP-10 units were rebuilt by the Illinois Central Gulf at Paducah, the Rock Island Railroad's Silvis, Illinois shops, Precision National Corp. at Mt. Vernon, Illinois, and Morrison-Knudsen at Boise, Idaho.
Volumes have been written about the internal and external differences between these rebuilt locomotives. Generally speaking, the earlier the rebuild, the more extensive the external modifications. As time went on the rebuilds became less and less through.
Conrail's 48 GP-8's were rebuilt by IGC, RI, and MK between 1976 and 1979. Although most of Conrail's GP-7's were of Penn Central origin, only a handful were considered worth rebuilding (25 of 239). While fully 11 of 14 from the Peoria and Eastern were rebuilt, along with 18 of 71 from the Erie Lackawanna. 4 of the Reading's 17 GP-7's were also rebuilt. None of the decrepit Jersey Central units were rebuilt.
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GP-8 5459 was rebuilt by Morrison Knudsen in 10/78 from CR 5930 originally Erie 1200 (8-50). It is seen here on one of the turntable tracks at Bethlehem Engine Terminal on March 31, 1983. |
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GP-8 5462 was rebuilt by Morrison Knudsen in 12/78 from CR 5838, originally RDG 636 (10-53). 5462 is seen on the DL&W mainline at Gravel Place, Pa on May 19, 1983. |
Conrail's 75 GP-10's were rebuilt by IGC, MK, and PNC in 1976 and 1978. All of the rebuilt GP-9's were of Penn Central origin, evenly split between NYC and PRR engines.
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GP-10 7575 pulls a train at Abrams Yard near King of Prussia, Pa. on Oct. 7, 1978. 7575 was rebuilt in 1976 by Paducah from CR 7237, originally PRR 7237 (10-59). Photo by Mike Szilagyi |
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GP-10 7565 was rebuilt in 1976 by Paducah from CR 7111, originally PRR 7111 (5-57). Seen at Abrams Yard near King of Prussia, Pa. March17, 1980 Photo by Mike Szilagyi |
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GP-10 7561 is the last unit in a wild lash up consisting of a GP-38, 2 B23-7's, 2 SW-900m's and the GP-10 leading a ballast train on May 6, 1991 Fairlawn Pa. This eclectic collection of units demonstrates how power short Conrail was in the early 1990s. GP-10 7561 was rebuilt in 1976 by Paducah from CR 7402, originally NYC 6002 (10-56). |